From 320fad49c5db9d65eb7ea6311858da34c7e5302d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20D=C3=A4schle?= <daniel.daeschle@gmail.com>
Date: Thu, 9 Apr 2020 19:23:49 +0200
Subject: [PATCH] checker: check enum

---
 vlib/v/ast/ast.v         | 11 +++++++++--
 vlib/v/checker/checker.v | 23 ++++++++++++++++++++---
 vlib/v/fmt/fmt.v         | 13 +++++++++++--
 vlib/v/gen/cgen.v        | 26 ++++++++++++++------------
 vlib/v/parser/parser.v   | 13 +++++++++----
 5 files changed, 63 insertions(+), 23 deletions(-)

diff --git a/vlib/v/ast/ast.v b/vlib/v/ast/ast.v
index 60bdec98bc..1645c65e12 100644
--- a/vlib/v/ast/ast.v
+++ b/vlib/v/ast/ast.v
@@ -494,12 +494,19 @@ mut:
 	typ       table.Type
 }
 
+pub struct EnumField {
+	name  string
+	pos   token.Position
+	exprs []Expr
+}
+
 pub struct EnumDecl {
 pub:
 	name          string
 	is_pub        bool
-	vals          []string
-	default_exprs []Expr
+	fields        []EnumField
+	// vals          []string
+	// default_exprs []Expr
 }
 
 pub struct AliasTypeDecl {
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index 67e85bde97..26a32708b2 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -560,6 +560,20 @@ pub fn (c mut Checker) return_stmt(return_stmt mut ast.Return) {
 	}
 }
 
+pub fn (c mut Checker) enum_decl(decl ast.EnumDecl) {
+	for field in decl.fields {
+		for expr in field.exprs {
+			match expr {
+				ast.IntegerLiteral {}
+				ast.PrefixExpr {}
+				else {
+					c.error("default value for enum has to be an integer", field.pos)
+				}
+			}
+		}
+	}
+}
+
 pub fn (c mut Checker) assign_stmt(assign_stmt mut ast.AssignStmt) {
 	c.expected_type = table.none_type	// TODO a hack to make `x := if ... work`
 	if assign_stmt.left.len > assign_stmt.right.len {
@@ -737,9 +751,6 @@ fn (c mut Checker) stmt(node ast.Stmt) {
 				c.stmts(it.else_stmts)
 			}
 		}
-		ast.DeferStmt {
-			c.stmts(it.stmts)
-		}
 		ast.ConstDecl {
 			mut field_names := []string
 			mut field_order := []int
@@ -776,6 +787,12 @@ fn (c mut Checker) stmt(node ast.Stmt) {
 				it.fields = ordered_fields
 			}
 		}
+		ast.DeferStmt {
+			c.stmts(it.stmts)
+		}
+		ast.EnumDecl {
+			c.enum_decl(it)
+		}
 		ast.ExprStmt {
 			etype := c.expr(it.expr)
 			c.expected_type = table.void_type
diff --git a/vlib/v/fmt/fmt.v b/vlib/v/fmt/fmt.v
index a0baa447a3..0d1e0aa250 100644
--- a/vlib/v/fmt/fmt.v
+++ b/vlib/v/fmt/fmt.v
@@ -208,8 +208,17 @@ fn (f mut Fmt) stmt(node ast.Stmt) {
 			}
 			name := it.name.after('.')
 			f.writeln('enum $name {')
-			for val in it.vals {
-				f.writeln('\t' + val)
+			for field in it.fields {
+				f.write('\t$field.name')
+				if field.exprs.len > 0 {
+					f.write(' = ')
+					for expr in field.exprs {
+						f.expr(expr)
+					}
+					f.writeln(',')
+				} else {
+					f.writeln('')
+				}
 			}
 			f.writeln('}\n')
 		}
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index 0423486733..559ac3e3bd 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -363,21 +363,23 @@ fn (g mut Gen) stmt(node ast.Stmt) {
 			g.defer_stmts << defer_stmt
 		}
 		ast.EnumDecl {
-			name := it.name.replace('.', '__')
+			enum_name := it.name.replace('.', '__')
 			g.typedefs.writeln('typedef enum {')
-			for j, val in it.vals {
-				if j < it.default_exprs.len {
-					g.typedefs.write('\t${name}_$val = ')
-					pos := g.out.len
-					g.expr(it.default_exprs[j])
-					expr := g.out.after(pos)
-					g.out.go_back(expr.len)
-					g.typedefs.writeln('$expr,')
-				} else {
-					g.typedefs.writeln('\t${name}_$val, // $j')
+			for field in it.fields {
+				g.typedefs.write('\t${enum_name}_$field.name')
+				if field.exprs.len > 0 {
+					g.typedefs.write(' = ')
 				}
+				for expr in field.exprs {
+					pos := g.out.len
+					g.expr(expr)
+					expr_str := g.out.after(pos)
+					g.out.go_back(expr_str.len)
+					g.typedefs.write('$expr_str')
+				}
+				g.typedefs.writeln(',')
 			}
-			g.typedefs.writeln('} $name;\n')
+			g.typedefs.writeln('} $enum_name;\n')
 		}
 		ast.ExprStmt {
 			g.expr(it.expr)
diff --git a/vlib/v/parser/parser.v b/vlib/v/parser/parser.v
index e158384bdd..88e96f5266 100644
--- a/vlib/v/parser/parser.v
+++ b/vlib/v/parser/parser.v
@@ -1848,15 +1848,19 @@ fn (p mut Parser) enum_decl() ast.EnumDecl {
 	name := p.prepend_mod(p.check_name())
 	p.check(.lcbr)
 	mut vals := []string
-	mut default_exprs := []ast.Expr
+	// mut default_exprs := []ast.Expr
+	mut fields := []ast.EnumField
 	for p.tok.kind != .eof && p.tok.kind != .rcbr {
 		val := p.check_name()
+		pos := p.tok.position()
 		vals << val
+		mut exprs := []ast.Expr
 		// p.warn('enum val $val')
 		if p.tok.kind == .assign {
 			p.next()
-			default_exprs << p.expr(0)
+			exprs << p.expr(0)
 		}
+		fields << ast.EnumField{val, pos, exprs}
 		// Allow commas after enum, helpful for
 		// enum Color {
 		// r,g,b
@@ -1876,8 +1880,9 @@ fn (p mut Parser) enum_decl() ast.EnumDecl {
 	return ast.EnumDecl{
 		name: name
 		is_pub: is_pub
-		vals: vals
-		default_exprs: default_exprs
+		// vals: vals
+		// default_exprs: default_exprs
+		fields: fields
 	}
 }